1
|
Thurgood LA, Best OG, Rowland A, Lower KM, Brooks DA, Kuss BJ. Lipid uptake in chronic lymphocytic leukemia. Exp Hematol 2021; 106:58-67. [PMID: 34896245 DOI: 10.1016/j.exphem.2021.12.193] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/02/2021] [Accepted: 12/05/2021] [Indexed: 11/19/2022]
Abstract
Many cancers rely on glucose as an energy source, but it is becoming increasingly apparent that some cancers use alternate substrates to fuel their proliferation. Chronic lymphocytic leukaemia (CLL) is one such cancer. Through the use of flow cytometry and confocal microscopy, low levels of glucose uptake were observed in the OSU-CLL and HG3 CLL cell lines relative to highly glucose-avid Raji cells (Burkitt's lymphoma). Glucose uptake in CLL cells correlated with low expression of the GLUT1 and GLUT3 receptors. In contrast, both CLL cell lines and primary CLL cells, but not healthy B cells, were found to rapidly internalise medium- and long-chain, but not short-chain, fatty acids (FAs). Differential FA uptake was also observed in primary cells taken from patients with unmutated immunoglobulin heavy variable chain usage (IGHV) compared with patients with mutated IGHV. Delipidation of serum in the culture medium slowed the proliferation and significantly reduced the viability of OSU-CLL and HG3 cells, effects that were partially reversed by supplementation with a chemically defined lipid concentrate. These observations highlight the potential importance of FAs in the pathogenesis of CLL and raise the possibility that targeting FA utilisation may represent a novel therapeutic and prognostic approach in this disease.
Collapse
Affiliation(s)
- Lauren A Thurgood
- Molecular Medicine and Genetics, College of Medicine and Public Health, Flinders University, Bedford Park, Australia.
| | - Oliver G Best
- Molecular Medicine and Genetics, College of Medicine and Public Health, Flinders University, Bedford Park, Australia
| | - Ashley Rowland
- Molecular Medicine and Genetics, College of Medicine and Public Health, Flinders University, Bedford Park, Australia
| | - Karen M Lower
- Molecular Medicine and Genetics, College of Medicine and Public Health, Flinders University, Bedford Park, Australia
| | - Doug A Brooks
- Cancer Research Institute, University of South Australia, Adelaide, Australia
| | - Bryone J Kuss
- Molecular Medicine and Genetics, College of Medicine and Public Health, Flinders University, Bedford Park, Australia
| |
Collapse
|
2
|
Karimi N, Karami Tehrani FS. Expression of SR-B1 receptor in breast cancer cell lines, MDAMB-468 and MCF-7: Effect on cell proliferation and apoptosis. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2021; 24:1069-1077. [PMID: 34804424 PMCID: PMC8591767 DOI: 10.22038/ijbms.2021.56752.12674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Accepted: 07/12/2021] [Indexed: 12/21/2022]
Abstract
OBJECTIVES High-density lipoprotein (HDL) is necessary for proliferation of several cells. The growth of many kinds of cells, such as breast cancer cells (BCC) is motivated by HDL. Cellular uptake of cholesterol from HDL which increases cell growth is facilitated by scavenger receptors of the B class (SR-BI). The proliferative effect of HDL might be mediated by this receptor. It is also believed that HDL has an anti-apoptotic effect on various cell types and promotes cell growth. This study was designed to investigate SR-BI expression, proliferation and apoptotic effect of HDL on human BCC lines, MCF-7 and MDA-MB-468. MATERIALS AND METHODS Real-time-PCR method was used to evaluate expression of SR-BI, and cholesterol concentration was measured using a cholesterol assay kits (Pars AZ moon, Karaj, Iran). Cell viability was assessed using the MTT test. To identify cell apoptosis, the annexin V-FITC staining test and caspase-9 activity assay were applied. RESULTS Treatment of both cell lines (MCF-7, MDA-MB-468) with HDL results in augmentation of SR-BI mRNA expression and also elevation of the intracellular cholesterol (P<0.01). HDL induced cell proliferation, cell cycle progression, and prevented activation of caspase-9 (P<0.05). We also demonstrated that inhibition of SR-B1 by BLT-1 could reduce cell proliferation, and induction of SR-B1 receptor by quercetin increased HDL-induced proliferation in both cell lines (P<0.05). CONCLUSION It can be concluded that alteration in HDL levels by SR-B1 activator (Quercetin) or inhibitor (BLT-1) may affect BCC growth and apoptosis induction.
Collapse
Affiliation(s)
- Neamat Karimi
- Department of Clinical Biochemistry, Cancer Research Laboratory, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Fatemeh Soghra Karami Tehrani
- Department of Clinical Biochemistry, Cancer Research Laboratory, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| |
Collapse
|
3
|
Kroiss M, Plonné D, Kendl S, Schirmer D, Ronchi CL, Schirbel A, Zink M, Lapa C, Klinker H, Fassnacht M, Heinz W, Sbiera S. Association of mitotane with chylomicrons and serum lipoproteins: practical implications for treatment of adrenocortical carcinoma. Eur J Endocrinol 2016; 174:343-53. [PMID: 26671975 DOI: 10.1530/eje-15-0946] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/15/2015] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Oral mitotane (o,p'-DDD) is a cornerstone of medical treatment for adrenocortical carcinoma (ACC). AIM Serum mitotane concentrations >14 mg/l are targeted for improved efficacy but not achieved in about half of patients. Here we aimed at a better understanding of intestinal absorption and lipoprotein association of mitotane and metabolites o,p'-dichlorodiphenylacetic acid (o,p'-DDA) and o,p'-dichlorodiphenyldichloroethane (o,p'-DDE). DESIGN Lipoproteins were isolated by ultracentrifugation from the chyle of a 29-year-old patient and serum from additional 14 ACC patients treated with mitotane. HPLC was applied for quantification of mitotane and metabolites. We assessed NCI-H295 cell viability, cortisol production, and expression of endoplasmic reticulum (ER) stress marker genes to study the functional consequences of mitotane binding to lipoproteins. RESULTS Chyle of the index patient contained 197 mg/ml mitotane, 53 mg/ml o,p'-DDA, and 51 mg/l o,p'-DDE. Of the total mitotane in serum, lipoprotein fractions contained 21.7±21.4% (VLDL), 1.9±0.8% (IDL), 8.9±5.5% (LDL1), 18.9±9.6% (LDL2), 10.1±4.0% (LDL3), and 26.3±13.0% (HDL2). Only 12.3±5.5% were in the lipoprotein-depleted fraction. DISCUSSION Mitotane content of lipoproteins directly correlated with their triglyceride and cholesterol content. O,p'-DDE was similarly distributed, but 87.9±4.2% of o,p'-DDA found in the HDL2 and lipoprotein-depleted fractions. Binding of mitotane to human lipoproteins blunted its anti-proliferative and anti-hormonal effects on NCI-H295 cells and reduced ER stress marker gene expression. CONCLUSION Mitotane absorption involves chylomicron binding. High concentrations of o,p'-DDA and o,p'-DDE in chyle suggest intestinal mitotane metabolism. In serum, the majority of mitotane is bound to lipoproteins. In vitro, lipoprotein binding inhibits activity of mitotane suggesting that lipoprotein-free mitotane is the therapeutically active fraction.
Collapse
Affiliation(s)
- Matthias Kroiss
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Dietmar Plonné
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Sabine Kendl
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Diana Schirmer
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Cristina L Ronchi
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Andreas Schirbel
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Martina Zink
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Constantin Lapa
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Hartwig Klinker
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Martin Fassnacht
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Werner Heinz
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| | - Silviu Sbiera
- Endocrine and Diabetes UnitDepartment of Internal Medicine IInfectiology UnitDepartment of Internal Medicine II, University Hospital Würzburg, Oberdürrbacher Street 6, 97080 Würzburg, GermanyComprehensive Cancer Center MainfrankenUniversity of Würzburg, Würzburg, GermanyDivision of Laboratory MedicineMedical Care Centre of Human Genetics Ulm, Ulm, GermanyDepartment of Nuclear MedicineUniversity Hospital Würzburg, Würzburg, GermanyClinical Chemistry and Laboratory MedicineUniversity Hospital Würzburg, Würzburg, Germany
| |
Collapse
|
4
|
Angius F, Spolitu S, Uda S, Deligia S, Frau A, Banni S, Collu M, Accossu S, Madeddu C, Serpe R, Batetta B. High-density lipoprotein contribute to G0-G1/S transition in Swiss NIH/3T3 fibroblasts. Sci Rep 2015; 5:17812. [PMID: 26640042 PMCID: PMC4671069 DOI: 10.1038/srep17812] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 10/19/2015] [Indexed: 01/08/2023] Open
Abstract
High density lipoproteins (HDLs) play a crucial role in removing excess cholesterol from peripheral tissues. Although their concentration is lower during conditions of high cell growth rate (cancer and infections), their involvement during cell proliferation is not known. To this aim, we investigated the replicative cycles in synchronised Swiss 3T3 fibroblasts in different experimental conditions: i) contact-inhibited fibroblasts re-entering cell cycle after dilution; ii) scratch-wound assay; iii) serum-deprived cells induced to re-enter G1 by FCS, HDL or PDGF. Analyses were performed during each cell cycle up to quiescence. Cholesterol synthesis increased remarkably during the replicative cycles, decreasing only after cells reached confluence. In contrast, cholesteryl ester (CE) synthesis and content were high at 24 h after dilution and then decreased steeply in the successive cycles. Flow cytometry analysis of DiO-HDL, as well as radiolabeled HDL pulse, demonstrated a significant uptake of CE-HDL in 24 h. DiI-HDL uptake, lipid droplets (LDs) and SR-BI immunostaining and expression followed the same trend. Addition of HDL or PDGF partially restore the proliferation rate and significantly increase SR-BI and pAKT expression in serum-deprived cells. In conclusion, cell transition from G0 to G1/S requires CE-HDL uptake, leading to CE-HDL/SR-BI pathway activation and CEs increase into LDs.
Collapse
Affiliation(s)
- Fabrizio Angius
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Stefano Spolitu
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Sabrina Uda
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Stefania Deligia
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Alessandra Frau
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Sebastiano Banni
- Divisions of Physiology, University of Cagliari, Cagliari, Italy
| | - Maria Collu
- Neuroscience and Clinical Pharmacology, University of Cagliari, Cagliari, Italy
| | - Simonetta Accossu
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| | - Clelia Madeddu
- Department of Biomedical Sciences, Department of Medical Sciences "Mario Aresu", University of Cagliari, Cagliari, Italy
| | - Roberto Serpe
- Department of Biomedical Sciences, Department of Medical Sciences "Mario Aresu", University of Cagliari, Cagliari, Italy
| | - Barbara Batetta
- Unit of Experimental Medicine, University of Cagliari, Cagliari, Italy
| |
Collapse
|
5
|
Lyu J, Imachi H, Fukunaga K, Yoshimoto T, Zhang H, Murao K. Roles of lipoprotein receptors in the entry of hepatitis C virus. World J Hepatol 2015; 7:2535-2542. [PMID: 26527170 PMCID: PMC4621467 DOI: 10.4254/wjh.v7.i24.2535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 08/07/2015] [Accepted: 09/28/2015] [Indexed: 02/06/2023] Open
Abstract
Infection by hepatitis C virus (HCV), a plus-stranded RNA virus that can cause cirrhosis and hepatocellular carcinoma, is one of the major health problems in the world. HCV infection is considered as a multi-step complex process and correlated with abnormal metabolism of lipoprotein. In addition, virus attacks hepatocytes by the initial attaching viral envelop glycoprotein E1/E2 to receptors of lipoproteins on host cells. With the development of HCV model system, mechanisms of HCV cell entry through lipoprotein uptake and its receptor have been extensively studied in detail. Here we summarize recent knowledge about the role of lipoprotein receptors, scavenger receptor class B type I and low-density lipoprotein receptor in the entry of HCV, providing a foundation of novel targeting therapeutic tools against HCV infection.
Collapse
|
6
|
Uda S, Spolitu S, Angius F, Collu M, Accossu S, Banni S, Murru E, Sanna F, Batetta B. Role of HDL in cholesteryl ester metabolism of lipopolysaccharide-activated P388D1 macrophages. J Lipid Res 2013; 54:3158-69. [PMID: 23956443 DOI: 10.1194/jlr.m042663] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Infections share with atherosclerosis similar lipid alterations, with accumulation of cholesteryl esters (CEs) in activated macrophages and concomitant decrease of cholesterol-HDL (C-HDL). Yet the precise role of HDL during microbial infection has not been fully elucidated. Activation of P388D1 by lipopolysaccharide (LPS) triggered an increase of CEs and neutral lipid contents, along with a remarkable enhancement in 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate-HDL uptake. Similar results were found in human monocyte-derived macrophages and monocytes cocultured with phytohemagglutinin-activated lymphocytes. Inhibition of cholesterol esterification with Sandoz-58035 resulted in 80% suppression of CE biosynthesis in P388D1. However, only a 35% decrease of CE content, together with increased scavenger receptor class B member 1 (SR-B1) protein expression, was found after 72 h and thereafter up to 16 passages of continuous ACAT suppression. Chronic inhibition blunted the effect of LPS treatment on cholesterol metabolism, increased the ratio of free cholesterol/CE content and enhanced interleukin 6 secretion. These results imply that, besides de novo biosynthesis and acquisition by LDL, HDL contributes probably through SR-B1 to the increased CE content in macrophages, partly explaining the low levels of C-HDL during their activation. Our data suggest that in those conditions where more CEs are required, HDL rather than removing, may supply CEs to the cells.
Collapse
Affiliation(s)
- Sabrina Uda
- Experimental Medicine Unit, University of Cagliari, Cagliari, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Twiddy AL, Cox ME, Wasan KM. Knockdown of scavenger receptor class B type I reduces prostate specific antigen secretion and viability of prostate cancer cells. Prostate 2012; 72:955-65. [PMID: 22025344 DOI: 10.1002/pros.21499] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Accepted: 09/19/2011] [Indexed: 01/22/2023]
Abstract
BACKGROUND Scavenger Receptor Class B Type I (SR-BI) facilitates influx of cholesterol to the cell from lipoproteins in the circulation. This influx of cholesterol may be important for many cellular functions, including synthesis of androgens. Castration-resistant prostate cancer tumors are able to synthesize androgens de novo in order to supplement the loss of exogenous sources often induced by androgen deprivation therapy. Silencing of SR-BI may impact the ability of prostate cancer cells, particularly those of castration-resistant state, to maintain the intracellular supply of androgens by removing a supply of cholesterol. METHODS SR-BI expression was knocked down using small interfering RNA in LNCaP and C4-2 cells. The effect of down-regulation of SR-BI on PSA production, cell toxicity, and cell viability was measured in both cell types. In addition, compensatory cholesterol synthesis activity was measured using the radiolabeled precursor, (14) C-acetate. RESULTS SR-BI protein expression is higher basally in C4-2 cells than LNCaP cells. Silencing of SR-BI expression to greater than 85% reduced PSA production in LNCaP and C4-2 SRBI-KD cells by 55% and 58% compared to negative control cells, respectively. SR-BI-KD C4-2 cells demonstrated significantly reduced cell viability (>25%) compared the NC cells. CONCLUSIONS The down-regulation of SR-BI significantly impacts PSA production of prostate cancer cells, as well as the viability of C4-2 cells in the presence and absence of HDL. This may indicate a deficiency in cholesterol availability to the androgen synthesis pathway or may implicate a role for SR-BI in prostate cancer signal transduction pathways.
Collapse
Affiliation(s)
- Alexis L Twiddy
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | |
Collapse
|
8
|
Uda S, Accossu S, Spolitu S, Collu M, Angius F, Sanna F, Banni S, Vacca C, Murru E, Mulas C, Diaz G, Batetta B. A lipoprotein source of cholesteryl esters is essential for proliferation of CEM-CCRF lymphoblastic cell line. Tumour Biol 2011; 33:443-53. [PMID: 22161086 DOI: 10.1007/s13277-011-0270-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 11/07/2011] [Indexed: 12/01/2022] Open
Abstract
Tumour are characterised by a high content of cholesteryl esters (CEs) stored in lipid droplets purported to be due to a high rate of intracellular esterification of cholesterol. To verify whether and which pathways involved in CE accumulation are essential in tumour proliferation, the effect of CE deprivation, from both exogenous and endogenous sources, on CEM-CCRF cells was investigated. Cholesterol synthesis, esterification and content, low-density lipoprotein (LDL) binding and high-density lipoprotein (HDL)-CE uptake were evaluated in cultured in both conventional and delipidated bovine serum with or without oleic or linoleic acids, cholesteryl oleate, LDL and HDL. High content of CEs in lipid droplets in this cell line was due to esterification of both newly synthesised cholesterol and that obtained from hydrolysis of LDL; moreover, a significant amount of CE was derived from HDL-CE uptake. Cell proliferation was slightly affected by either acute or chronic treatment up to 400 μM with Sz-58035, an acyl-cholesteryl cholesterol esterification inhibitor (ACAT); although when the enzyme activity was continuously inhibited, CE content in lipid droplets was significantly higher than those in control cells. In these cells, analysis of intracellular and medium CEs revealed a profile reflecting the characteristics of bovine serum, suggesting a plasma origin of CE molecules. Cell proliferation arrest in delipidated medium was almost completely prevented in the first 72 h by LDL or HDL, although in subsequent cultures with LDL, it manifested an increasing mortality rate. This study suggests that high content of CEs in CEM-CCRF is mainly derived from plasma lipoproteins and that part of CEs stored in lipid droplets are obtained after being taken up from HDL. This route appears to be up-regulated according to cell requirements and involved in low levels of c-HDL during cancer. Moreover, the dependence of tumour cells on a source of lipoprotein provides a novel impetus in developing therapeutic strategies for use in the treatment of some tumours.
Collapse
Affiliation(s)
- Sabrina Uda
- Department of Science and Biomedical Technologies, University of Cagliari, Cagliari, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Xing Y, Cohen A, Rothblat G, Sankaranarayanan S, Weibel G, Royer L, Francone OL, Rainey WE. Aldosterone production in human adrenocortical cells is stimulated by high-density lipoprotein 2 (HDL2) through increased expression of aldosterone synthase (CYP11B2). Endocrinology 2011; 152:751-63. [PMID: 21239432 PMCID: PMC3040046 DOI: 10.1210/en.2010-1049] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Adrenal aldosterone production is regulated by physiological agonists at the level of early and late rate-limiting steps. Numerous studies have focused on the role of lipoproteins including high-density lipoprotein (HDL) as cholesterol providers in this process; however, recent research suggests that HDL can also act as a signaling molecule. Herein, we used the human H295R adrenocortical cell model to study the effects of HDL on adrenal aldosterone production and CYP11B2 expression. HDL, especially HDL2, stimulated aldosterone synthesis by increasing expression of CYP11B2. HDL treatment increased CYP11B2 mRNA in both a concentration- and time-dependent manner, with a maximal 19-fold increase (24 h, 250 μg/ml of HDL). Effects of HDL on CYP11B2 were not additive with natural agonists including angiotensin II or K(+). HDL effects were likely mediated by a calcium signaling cascade, because a calcium channel blocker and a calmodulin kinase inhibitor abolished the CYP11B2-stimulating effects. Of the two subfractions of HDL, HDL2 was more potent than HDL3 in stimulating aldosterone and CYP11B2. Further studies are needed to identify the active components of HDL, which regulate aldosterone production.
Collapse
MESH Headings
- Adrenal Cortex/cytology
- Adrenal Cortex/metabolism
- Aldosterone/metabolism
- Calcium/metabolism
- Calcium Signaling/physiology
- Cell Line
- Cholesterol, HDL/pharmacology
- Cytochrome P-450 CYP11B2/genetics
- Cytochrome P-450 CYP11B2/metabolism
- Gene Expression Regulation, Enzymologic/drug effects
- Gene Expression Regulation, Enzymologic/physiology
- Humans
- Nuclear Receptor Subfamily 4, Group A, Member 2/genetics
- Nuclear Receptor Subfamily 4, Group A, Member 2/metabolism
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Scavenger Receptors, Class B/genetics
- Scavenger Receptors, Class B/metabolism
Collapse
Affiliation(s)
- Yewei Xing
- Department of Physiology, Medical College of Georgia, 1120 15th Street, CA-3094, Augusta, Georgia 30912, USA
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Sekine Y, Demosky SJ, Stonik JA, Furuya Y, Koike H, Suzuki K, Remaley AT. High-density lipoprotein induces proliferation and migration of human prostate androgen-independent cancer cells by an ABCA1-dependent mechanism. Mol Cancer Res 2010; 8:1284-94. [PMID: 20671065 DOI: 10.1158/1541-7786.mcr-10-0008] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Androgen deprivation therapy for prostate cancer leads to a significant increase of high-density lipoprotein (HDL), which is generally viewed as beneficial, particularly for cardiovascular disease, but the effect of HDL on prostate cancer is unknown. In this study, we investigated the effect of HDL on prostate cancer cell proliferation, migration, intracellular cholesterol levels, and the role of cholesterol transporters, namely ABCA1, ABCG1, and SR-BI in these processes. HDL induced cell proliferation and migration of the androgen-independent PC-3 and DU145 cells by a mechanism involving extracellular signal-regulated kinase (ERK) 1/2 and Akt, but had no effect on the androgen-dependent LNCaP cell, which did not express ABCA1 unlike the other cell lines. Treatment with HDL did not significantly alter the cholesterol content of the cell lines. Knockdown of ABCA1 but not ABCG1 or SR-BI by small interfering RNA (siRNA) inhibited HDL-induced cell proliferation, migration, and ERK1/2 and Akt signal transduction in PC-3 cells. Moreover, after treatment of LNCaP cells with charcoal-stripped fetal bovine serum, ABCA1 was induced ∼10-fold, enabling HDL to induce ERK1/2 activation, whereas small interfering RNA knockdown of ABCA1 inhibited HDL-induced ERK1/2 activation. Simvastatin, which inhibited ABCA1 expression in PC-3 and DU145 cells, attenuated HDL-induced PC-3 and DU145 cell proliferation, migration, and ERK1/2 and Akt phosphorylation. In human prostate biopsy samples, ABCA1 mRNA expression was ∼2-fold higher in the androgen deprivation therapy group than in subjects with benign prostatic hyperplasia or pretreatment prostate cancer groups. In summary, these results suggest that HDL by an ABCA1-dependent mechanism can mediate signal transduction, leading to increased proliferation and migration of prostate cancer cells.
Collapse
Affiliation(s)
- Yoshitaka Sekine
- Lipoprotein Metabolism Section, Pulmonary and Vascular Medicine Branch, NHLBI, NIH, Building 10, Room 8N224, 9000 Rockville Pike, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | |
Collapse
|
11
|
Nishiuchi T, Murao K, Imachi H, Yu X, Dobashi H, Haba R, Ishida T. Scavenger receptor class BI mediates the anti-apoptotic effect of erythropoietin. Ann Med 2010; 42:151-60. [PMID: 20156043 DOI: 10.3109/07853891003601556] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A scavenger receptor of the B class (SR-BI)/human homolog of SR-BI, CD36, and LIMP II analogous-1 (CLA-1), has been identified as a receptor for high-density lipoprotein (HDL). Mice lacking SR-B1 develop anemia, plausibly explained by the observation that the erythrocyte life-span in these animals is reduced. Erythropoietin (EPO) is known to promote survival of erythroid cells, in large part through protection from apoptosis. We have examined the role of EPO on hSR-BI/CLA-1 expression and erythrocyte apoptosis. Endogenous expression of hSR-BI/CLA-1 was increased by exposure to EPO. EPO increased transcriptional activity of hSR-BI/CLA-1 promoter. The stimulatory effect of EPO on hSR-BI/CLA-1 promoter activity was abrogated by LY294002, specific inhibitor of phosphatidylinositol-3 kinase (PI3K). Constitutively active Akt stimulates the activity of the hSR-BI/CLA-1 promoter and a dominant-negative mutant of Akt abolished the ability of EPO to stimulate promoter activity. Finally, EPO in combination with HDL protected the cell from apoptosis, which suggests that hSR-BI/CLA-1 induced by EPO might contribute to the erythrocyte life-span.
Collapse
Affiliation(s)
- Takamasa Nishiuchi
- Division of Endocrinology & Metabolism and Hematology, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe Miki-Cho, Kita-gun, Kagawa, 761-0793, Japan
| | | | | | | | | | | | | |
Collapse
|
12
|
Murao K, Imachi H, Yu X, Cao WM, Muraoka T, Dobashi H, Hosomi N, Haba R, Iwama H, Ishida T. The transcriptional factor prolactin regulatory element-binding protein mediates the gene transcription of adrenal scavenger receptor class B type I via 3',5'-cyclic adenosine 5'-monophosphate. Endocrinology 2008; 149:6103-12. [PMID: 18755803 DOI: 10.1210/en.2008-0380] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor that regulates prolactin promoter activity in the rat anterior pituitary. The PREB protein is not only expressed in the anterior pituitary but also in the adrenal gland. However, the role of PREB in the adrenal gland is not clearly understood. Scavenger receptor class B type I (SR-BI) is a receptor for high-density lipoprotein that mediates the cellular uptake of high-density lipoprotein-cholesteryl ester and is a major route for cholesterol delivery to the steroidogenic pathway in the adrenal gland. In the present study, we have examined the role of PREB in regulating SR-BI. SR-BI expression was found to be regulated by cAMP, which stimulated the expression of PREB in a dose-dependent manner. Conversely, overexpression of PREB using a PREB-expressing adenovirus increased the expression of the SR-BI protein in the adrenocortical cell line Y-1. In addition, PREB induced the expression of the luciferase reporter protein that was under the control of the SR-BI promoter. EMSA showed that PREB mediates its transcriptional effect by binding to the PREB-responsive cis-element of the SR-BI promoter. Finally, we used small interfering RNA to inhibit PREB expression in the Y-1 cells and demonstrated that the knockdown of PREB expression attenuated the effects of cAMP on SR-BI expression. In summary, our data showed that in the adrenal gland, PREB regulates the transcription of the SR-BI gene via cAMP.
Collapse
Affiliation(s)
- Koji Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa 761-0793, Japan.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Stern JL, Slobedman B. Human cytomegalovirus latent infection of myeloid cells directs monocyte migration by up-regulating monocyte chemotactic protein-1. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2008; 180:6577-85. [PMID: 18453576 DOI: 10.4049/jimmunol.180.10.6577] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Following primary infection, human cytomegalovirus (HCMV) establishes a latent infection in hematopoietic cells from which it reactivates to cause serious disease in immunosuppressed patients such as allograft recipients. HCMV is a common cause of disease in newborns and transplant patients and has also been linked with vascular diseases such as primary and post-transplant arteriosclerosis. A major factor in the pathogenesis of vascular disease is the CC chemokine MCP-1. In this study, we demonstrate that granulocyte macrophage progenitors (GMPs) latently infected with HCMV significantly increased expression of MCP-1 and that this phenotype was dependent on infection with viable virus. Inhibitors of a subset of G(alpha) proteins and PI3K inhibited the up-regulation of MCP-1 in latently infected cultures, suggesting that the mechanism underlying this phenotype involves signaling through a G-protein coupled receptor. In GMPs infected with the low passage viral strain Toledo, up-regulated MCP-1 was restricted to a subset of myeloid progenitor cells expressing CD33, HLA-DR, and CD14 but not CD1a, CD15, or CD16, and the increase in MCP-1 was sufficient to enhance migration of CD14(+) monocytes to latently infected cells. Latent HCMV-mediated up-regulation of MCP-1 provides a mechanism by which HCMV may contribute to vascular disease during the latent phase of infection or facilitate dissemination of virus upon reactivation from latency.
Collapse
Affiliation(s)
- J Lewis Stern
- Centre for Virus Research, Westmead Millennium Institute and the University of Sydney, Westmead, NSW, Australia
| | | |
Collapse
|
14
|
Miura SI, Matsuo Y, Saku K. Jun N-terminal kinase inhibitor blocks angiogenesis by blocking VEGF secretion and an MMP pathway. J Atheroscler Thromb 2008; 15:69-74. [PMID: 18385538 DOI: 10.5551/jat.e496] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
AIM The excessive proliferation and migration of vascular smooth muscle cells (SMCs) and angiogenesis of endothelial cells (ECs) participate in the growth and instability of atherosclerotic plaques. It is unclear whether Jun N-terminal kinase (JNK) is pro-or anti-atherogenic. METHODS We examined the direct effect of JNK inhibitor (JNK-I) on the proliferation and formation of tubes by human coronary SMCs and human coronary ECs. RESULTS Culture medium from JNK-I-treated SMCs prevented ECs from forming tubes in an in vitro model of angiogenesis indirectly by reducing the amount of vascular endothelial growth factor (VEGF) released from SMCs. In addition, JNK-I attenuated the expression of pro-matrix metalloproteinase-2 in ECs. When added back to the medium of SMCs treated with JNK-I, VEGF blocked the inhibitory effect on the formation of tubes. CONCLUSION Our results indicate JNK-I to have a direct anti-atherogenic effect in SMCs and ECs.
Collapse
Affiliation(s)
- Shin-ichiro Miura
- Department of Cardiology, Fukuoka University School of Medicine, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, Japan.
| | | | | |
Collapse
|
15
|
Iwasaki Y, Nishiyama M, Taguchi T, Kambayashi M, Asai M, Yoshida M, Nigawara T, Hashimoto K. Activation of AMP-activated protein kinase stimulates proopiomelanocortin gene transcription in AtT20 corticotroph cells. Am J Physiol Endocrinol Metab 2007; 292:E1899-905. [PMID: 17341551 DOI: 10.1152/ajpendo.00116.2006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Starvation is known to activate the hypothalamo-pituitary-adrenal (HPA) axis, a representative antistress system in the living organism. In this study, we investigated in vitro whether activation of the AMP-activated protein kinase (AMPK), which is known to occur in intracellular energy depletion, influences the expression of POMC gene that encodes adrenocorticotropin. We first confirmed that each subunit of AMPK was expressed in the AtT20 corticotroph cell line. We then found that AICAR, a cell-permeable AMP analog and an activator of AMPK, potently stimulated the 5'-promoter activity of POMC gene in a dose-dependent manner. The effects were promoter specific because AICAR enhanced the AP1-mediated POMC promoter activities but did not influence other transcription factor-induced transcription. The effect of AICAR on POMC gene transcription was completely eliminated by specific AMPK inhibitor compound C or by dominant negative AMPK, whereas overexpression of constitutively active AMPK mimicked the effect of AICAR. Finally, experiments using specific kinase inhibitors suggested that the PI 3-kinase-mediated signaling pathway is at least partly involved in the effect. Our results suggest that intracellular energy depletion with the resultant activation of AMPK directly stimulates the HPA axis at the pituitary level by increasing the expression of POMC gene.
Collapse
Affiliation(s)
- Yasumasa Iwasaki
- Department of Endocrinology, Metabolism, and Nephrology, Kochi Medical School, Kochi University, Kohasu, Japan.
| | | | | | | | | | | | | | | |
Collapse
|